An exploration of wild & interesting places in Ireland and their western European/American flora and fauna…
Some images in this report are enlargeable. Click image where you see this symbol to get a larger view.
Evidence indicating a
wind based trans Atlantic
restocking of Irish flora.
A. The Plant:
The plant is, of course, the beautiful exotic and evasive Spiranthes romanzoffiana. To those unfamiliar with the species let us describe it as a rare and sporadic (but predictable) member of the Irish and Scottish flora which we introduce with a series of typical flowers, this time taken from Lough Conn, Co. Mayo. It is a classic member of the Spiranthes genus with spiral florets curling around a stem of up to 0.4 m height. The photos shown below represent the best samples recorded this year and all are from Mayo lakes.We have been studying this species for 10 years, more or less since we first became aware of its occurrence around Lough Allen… further east in Co. Leitrim. This location almost vied with Lough Conn for a wide distribution of the species but it was also notoriously very variable in water level and in latter years (with increasing Summer rains) its very survival in L. Allen became doubtful. Indeed over the period from 2004 - 2016 its numbers varied from 1 to almost 300 discovered plants. This was not a steady decline but rather a random variation from year to year. All plants occurred on known shoreline sites mainly on the eastern and northern shore of L. Allen. The widely varying water height (it is controlled by sluices) initially suggested to us the idea that these plants were originating from seed floating on the water.We moved from L. Allen, but maintaining our interest in the species, we started to explore the hypothesis of this beautiful species, which had always been seen as an Atlantic species, actually being re-seeded on a continuous basis by wind borne seed from North America — where it is a widespread part of the Canadian and US flora. This ‘curiosity’ over the past two years (we hope) has borne fruit.
B. This Report:
Great care has been taken both with the plants (they are protected by Irish law) and with the interpretation of the evidence. We have jumped to a hypothesis but we have NOT jumped to a conclusion! In fact we feel a bit stupid sometimes for not recognising the obvious! As you can see we are not presenting this case in a dry technical format but (hopefully) in a manner that reflects our excitement with the plants and their distribution in Ireland. But this does not mean we have not hunted and collected (images) and walked numerous miles of wet muddy or stony shoreline. We have! But what is important to www.WildWest.ie is to share this information widely so as to satisfy the many keen European botanists who have traveled to the west of Ireland to observe and record this species. But, perhaps even more important, is our zeal to ensure this plant is well protected and encouraged to survive in our little part of the planet. Whilst a widespread species in Canada and USA it does not occur in Europe or Asia apart from here and Scotland. (Many books, old and new, refer to a continuing occurrence in Dartmoor in Devon… this is long gone and is an unfortunate example of books repeating errors!). It only occurs on this side of the Atlantic in Ireland and Scotland and very much in a concentrated zone between Galway in Ireland and The Western Isles of Scotland — where the strong Atlantic winds blow!
Presenting the evidence:
There is a lot of information to get across. We want you to come to the same conclusion as us. Getting to know another locality intensively has been a rewarding experience; we used to get emotionally drained when signs from Lough Allen seemed to indicate that the species was dying out. But, it always came back. Where did it come back from? Our evidence is all traditional naturalists’ approach to observation, wondering why, and then interpreting what we have seen on the ground over many years. We have not studied the DNA evidence though we are attentive to some of it — and also the way that it can be misconstrued . By studying the plant distribution, the fertilisation, the vegetative reproduction, the almost universal absence of seed, and (most importantly) the major importance of weather. The mystery of climate change is as clearly seen in S. romanzoffiana as it is anywhere! So this story can be viewed as a detective story but all the evidence is rock solid and derived from years of work which has really been brought to a conclusion by the past 2 years observations in a different and distinctive habitat… L. Conn.
Photography is an essential stock in trade. Without good cameras it would be hard to collect and collate this evidence. Therefore, we present numerous photographs. This harks back to L. Allen, in ways, when we feared that this species might leave the west of Ireland just as it has largely disappeared from the south of Ireland. But our research in L. Conn has provided confidence that it is a species that is reasonably secure here and our growing knowledge as to how it survives here backs up that confidence — but it still needs respect and conservation with a growing greener Irish farming sector that has the tools and commitment to provide this.As you will see there are numerous photographs on this page. These are presented for several reasons:•as a record of a plant which while maybe not critically rare is decidedly locally distributed and may occur where landowners are not expecting to find a protected species.•they present a clearer image as to what we believe is occurring in the ecology and distribution both locally and across the Atlantic.•Because of the number of the photographs we have had to reduce the size so some may be a bit small to be ‘readable’. Look out for the symbol as this will indicate that there is a much larger version of that image available at a click which will show the missing detail we attribute to that particular image.
C. The Evidence:
History of Worldwide distribution.
Of course, it is not worldwide, just North America and Ireland and Scotland. We have often asked learned botanists ‘how long has it been in Ireland’ and to their credit they normally say that this is not known at present. As you can see from the gallery at the top, this can be quite a striking plant which is very strongly associated with shorelines and islands where churches and graveyards may also occur. If it had been present as a fully native species one would have thought some scholarly writers might have celebrated its existence over the millennia. But NO such record exists.However Ireland did play a significant role in the history of this species with the first specimens being recorded by botanist James Drummond at Castletown Berehaven in 1810 on the seashore near the Big House! Interestingly this is a habitat that the species is not known for now as it is totally associated with freshwater lake shores in north west Ireland. Nor are they particularly associated with the sea. The only common factor with this West Cork record is that Spiranthes romanzoffiana is now normally found in Ireland and Scotland at low altitude — why, we do not know! This is not an adaptable species on this side of the Atlantic. (See the Section on Habitats and Topography.)At the other extreme of its distribution this plant was finally botanically classified on an island in a chain of islands stretching from Alaska into the Pacific. It was found here and named after the sponsor of the explorer who discovered it with its full proper modern name, Spiranthes romanzoffiana Cham. Romanzoff was the Governor of Kamchatka (where it doesn’t occur) and Chamisso was the hired botanist on board. This discovery was the first recognised occurrence in North America. One presumes it was present in large numbers as it is today or even much more numerous. Why had it been missed? The official Red Data Book is happy to regard the species as ‘Not Under Risk’ in North America today. If our theory, that the plants in Ireland or Scotland are derived from American seed is true, then it may not be under too much risk in Ireland but it still should be left unharmed and conserved wherever it appears. It will enrich our biodiversity, protect our shores and lakes, and ensure clean water!
Personal Experience of the Irish Distribution.
Spiranthes romanzoffiana was first identified in this region at Lough Allen by a local Landowner/botanist in the North-east corner of the lake while doing some research on the ecology of the area in about 2003. It was subsequently found, in good numbers on a farm on the western side of the lake, and identified by a National Parks and Wildlife Ranger for the North West region.We moved to the area in 2002, and heard about Spiranthes in 2007 when doing some birdwatching around the lake. We first saw this species on a tiny island just off the East shore of Lough Allen, in July 2008. This was a rocky ‘Spit’ much used by breeding Black-headed and Common Gulls, and was very susceptible to flooding. Two small specimens were found here. We intensified our search in many areas around the lake, and found upwards of 300 specimens in varied habitats. See map (RIGHT) for distribution in that year, which we put up on the website www.loughallenbasin.com. We were advised by some conservationists not to put in grid references for the plants, as they are a protected species and there could have been a risk of damage by people coming to search for them. But we have always seen more damage done by lack of awareness than good knowledge. Many are also on private land but these people almost universally were curious, pleased and happy to protect the plants, and we never had a problem in working with landowners.The following year, 2009, we eagerly set out in early July to search for Spiranthes, but, depressingly, the weather and water levels were unfavourable. In all the sites where we searched, only one small specimen was found in the north east of the lake. In following years, the numbers varied from 30 to 85. But never since did we get the large numbers which were seen in 2008.In 2013, while we were awaiting the arrival of three botanists from the Czech Republic to see and photograph Spiranthes, we found that the location we had intended to bring them to had been damaged by cattle and the flowers ruined. We started searching another area, a short distance away, which was a grassy, boggy area raised about 60cm above the ‘normal’ height at which we had seen the plants up to this. We had not seen Spiranthes in this area, though we had walked through it many times, and it made us realise that Spiranthes could occur in places higher up on the shore than we expected. Very often, plants are found on the same ‘line’ along the shore, consistent with the water level at the time their seeds were deposited. These new plants were of good size and ideal for our visitors to photograph. We studied these plants over a period of 2½ years, and they formed the basis for our ‘Spiranthes study’ on the growth of lateral buds and their life cycle existence throughout the winter months, even surviving submersion in c. 40cm of water. See Spiranthes Study photos 2013-2014 HERE We had heard of Spiranthes being found in good numbers on Mayo lakes (from research work done at the National Botanic Gardens) and we have surveyed and counted Spiranthes there since 2011. Lough Cullin had very good numbers, but numbers have decreased somewhat due to some shore and field clearing. Lough Conn has very good numbers; however these are sometimes difficult to locate as access can be difficult and often involves a lot of scrambling for some distance along a shoreline with many obstacles! A number of ‘New’ locations’ were found this year (2017) around Lough Conn. Some of these areas are not accessible to animals and therefore not so susceptible to damage. However, the heavy rains in August and September did flood much of the shoreline where they grow.Levally Lough, close to Lough Cullin, was one other place in Mayo where they have been found (and surveyed by a local botanist) but in small numbers. We just found two specimens on an open, easily accessed stony shore, but haven’t seen any there recently?
RIGHT: Distribution of Spiranthes romanzoffiana around Lough Allen, 2008
The other locations where we have personally seen Spiranthes growing include the north shore of Lough Corrib (many thanks to Sorcha who first showed us 7 specimens a few years ago). There are historical reports of Spiranthes being found in other locations around Lough Corrib, and also on Lough Mask, but we were unable to find any, or reports of any recent sightings.There have been occasional reports of Spiranthes being found in the South west, but unfortunately, no definite locations, or contacts. It would be fascinating to find Spiranthes today in the place where James Drummond first found this species, on a sandy beach in Castletownbere, in West Cork?
Habitat and topography of Irish occurrences.
It seems that the places and the situations in which Spiranthes occurs in Ireland may be quite different from the patterns often shown in North America. If you look at American Botanical sites they will often characterise this plant’s habitat as ‘bogland’. We have never found this species in a typical Irish bog. The example cited above doesn’t even look like a bog. In fact we didn’t know it was a bog until we installed protective cages around the 4 specimens we chose to monitor in regard to vegetative reproduction over a few years. However this was the most unusual site we have ever come across. It was higher than all other sites in being significantly above ‘normal’ Summer water level and it was some distance from the shore also.We can list Lough Allen’s normal Habitats as follows:•Rocky Island or headlands. In among very bouldery shores and associated especially with Lysimachia nummularia and stunted Alder trees.•Rich Grassy shores. Often at the back of sheltered bays and often under newly sprouting Alder copses. Shore has to be very flat if many Spiranthes are to be found in among small trees. •In sheltered south facing shores with little grazing. Rich flora including Lysimachia vulgaris,Anagellis arvensis and Sisyrinchium bermudiana (another amphi-Atlantic rarity).•Large stretches of flat managed shoreline grazing with sandy/silty soil with pools and exposed areas where seeds may germinate. Can be very good but unreliableAll theses sites on all shores of Lough Allen are consistently very close to water level, sometimes slightly above it or often underwater! The pattern of occurrence fits in perfectly with the concept of seeds floating in from the lakeshore. In Lough Allen the east and northeast shores were the most prolific with several suitable sites; this could be construed as facing the prevailing wind and more likely to receive wind/water borne seed.Habitat and topography of American occurrences.We have always been interested in ‘our cousins’ in America. Spiranthes romanzoffiana is, of course, primarily a species of North America. Its occurrence on this side of the Atlantic seems almost an afterthought, as is its absence from eastern Siberia. It was discovered by a Russian expedition, exploring what was then Russia, so one would think it should be there but it isn’t. However, it is clear that our stock emanates from that side of the Atlantic.Two outstanding features come to our attention— firstly photographs showing large groups of flowering specimens are often seen in North America. Secondly, it is widely dispersed across the continent from the boreal zone right down to southern California. There are also many other quite closely related Spiranthes species in North America/Canada, whereas Ireland has only two species. Spiranthes spiralis being a fairly widespread diminutive orchid that is found on coastal grasslands and machair, quarries, mainly in the western half of the country, and has no presence in America at all!In this section we have briefly looked at the occurrence of S. romanzoffiana in North America. As well as growing from coast to coast it also has a very varied habitat — as these pictures show. We show some specimens just to display the familiar plant in an unfamiliar setting but use other images to show the varied settings (particularly altitude) at which the species is found in Canada and America. It ranges from wet climates and marshes (Newfoundland and New York on the RIGHT) to mountains and volcanic areas, to fens and swamps. It still seems to need some water nearby. Warmer conditions in North America clearly facilitate the growth and flowering of the plant and the subsequent production of seeds.
The altitude shown in these pictures varies from sea level in Newfoundland to nearly 2000 m. in California.
As you can see there is a wide variety of habitats and environments from the cool Atlantic conditions very like ours to the mild boreal and warmer climes of California. By facies we mean all the various factors that can affect plant life. These include not just aspect but also soil and rock type, availability of water, avoidance of flooding, warmth, fertilising insects, lack of disturbance and a low natural vegetation height to permit the young shoots to emerge and prosper.
We are more interested, in this section, in the nature of the particular place where these varied botanists recorded them, rather than the plants themselves. In Ireland we used to feel that many of our specimens faced into the setting sun or the prevailing wind. This was based on Lough Allen observation and may have been a bit misleading as we have since found them widely located on shores of differing aspects all around Lough Conn — which is a much larger study population. We are awaiting further information from the people behind these photographs and will they will undoubtedly have some good stories to tell. There is something about this plant that brings out the best in people? Also, while abundant in certain sites, in other areas people have had to hunt hard for their trophy shot — just like in Ireland!
Condition of Plants
The condition of plants we have seen in the photographs, and we have reviewed many, varies considerably from climate to climate and this answers one of the fundamental questions we are hoping to answer in this section. The North American specimens are the same species as ours and significant difference in abundance and vigour of the plants may simply reflect the climate they are growing in. If growing on the cool North Atlantic shore, like in Newfoundland, they could be stunted and low growing with much reduced inflorescences as we often find in Ireland. However Gene Herzberg’s photo and comments establish that they can be strong and fertile plants also. He comments on his photograph as being… “part of a much larger population.“ In other settings, in surprising locations, they obviously enjoy a much warmer climate. One photograph, which we are unable to publish at present, shows a single solitary specimen growing high up on a apparently dry mountain slope in Wyoming — with the photographer expressing great delight in recording his latest trophy! Warmth will encourage plant growth and will clearly facilitate seed production. In North America the plants flower at roughly the same time as in Ireland, July/August, but in many of the southern States and warmer Canadian provinces they may still have a lengthy period of dry weather in which to generate their seeds and disperse them into the wind. We hope to establish even further good contacts with Spiranthes watchers in North America and get more insights into their local populations and their habitats.
In North America, Spiranthes romanzoffiana grows from sea level up to 2000 m. and from glorious sunshine to the wet muggy climates of Labrador and the Aleutian island of Unalaska in the North Pacific. In most places they seem to thrive and are in an environment that always seems to have some association with water, be it residual water in a dry fen or a dry pond or just a damp atmosphere beside the sea in Grate’s Harbour, Newfoundland. In Minnesota they are occasional, as in Ireland, and the photographer was delighted to obtain an image with 3 specimens. This looks like a lush forested area and quite likely the scarcity was due to other factors apart from climate?The specimens we have seen from Unalaska do seem to be small in size both when recorded initially by Chamisso as well as in modern studies of the species there. It is described as flowering straight from the ground and growing on sparsely vegetated arid areas — very much like some Irish specimens and probably a sign that the species is at the extreme edge of its range at that location also. It is very strange that this is the first location the species was described from and it is such a marginal location? This probably reflects the fact that avid naturalists were exploring new territory and recording everything they saw.The climate of Unalaska is cold and wet but not as extreme or severe as mainland Alaska. Temperatures range from 22°C Maximum in August to -12°C in Winter. Unalaska lies between 53° and 54° North, a latitude identical to Ireland’s Spiranthes province!
Mapping studies. Why?
With rare plant species it is always very important to record numbers and locations accurately. There is a balance to be found between secrecy and sharing sensitive information. We have to be discreet if the landowners requires that but, in general, we feel it is better to let people know what they have on their land or in their local patch. Over 13 years we have shared and received botanical advice and this has always been respected. The greatest damage we have ever seen to a vulnerable site has, surprisingly, been by a group of botanists who did not know exactly where they were going and accidentally walked on the plants they were looking for! We are very happy to meet overseas visitors and guide them to see our beautiful orchids. We have not yet had any botanists coming from North America to see S. romanzoffiana, but, then, why would they?
Coming from a background of biometrics it is natural to assess a population and want to know whether they are spreading or declining, whether they are producing other colonies or neighbouring plants, or whether there are as yet undiscovered new colonies just around the corner. L. Conn has been a revelation to us over the last few years. Nowadays we use a hand-held high sensitivity augmented GPS system with a claimed accuracy in good conditions of 2 m., more probably 3 m., but this can be less depending on forest conditions, cliffs, weather or any other factor that will reduce good satellite reception. The core benefits of monitoring a population of plants can be summarised as follows:•it provides a readily exchangeable database and map which can be shared with other researchers where this is appropriate.•changes in population numbers and distribution can be readily detected and monitored.•along with satellite images and open source mapping it can often pinpoint a habitat/aspect preference for the species in question which can then be used to discover further occurrences.•we often use GPS to count specimens that are too close together to be resolved within the systems accuracy restraints. This does lead to a distinct record and accurate count for every plant!•by and large all data we have shared has been respected and led to protection of the plants rather than any harm.
Mapping studies of recent Irish finds…
A lot of our work on L. Allen was done with a less precise GPS than now used. Patterns of seed placement were not so clear on any maps produced but were, of course, very striking visually. L. Allen Spiranthes sites are often in bays or headlands with very curved shorelines. Both on rocky shores and on muddy shores this curve has often been mirrored, when specimens were prolific, by matching contours of new emerging orchids. (Call them Isospires?) The main exception to this pattern is where the land the Spiranthes are emerging on is essentially flat, i.e. wet, often with shallow pools. Then the emerging plants can be widely dispersed but there is still often a micro pattern where new S. romanzoffiana plants cluster around small shallow pools. In L. Cullin, south of L. Conn this pattern is reversed in a large shallow bay on the north east corner where sand and silt is being deposited with subsequent conversion to a reed ‘forest’. During this transition a sandbank, or island, may form which emerges from the water before the bay dries out. On this, along with a signature rock or Alder tree, many Spiranthes will initially appear. This is a rapidly evolving process with the islands quickly becoming too shrubby and the whole bay drying out and becoming covered by reeds. The Spiranthes will survive in here for a time but it ceases to be an ideal habitat for newly emerging plants.
Recent mapping work on Lough Conn and the patterns it shows.
Lough Conn and surrounding lakes is an area we have been exploring for the past 4 years, particularly intensively in 2016 and 2017. It is different from L. Allen in that S. romanzoffiana seems to be happy to grow on all sides of the lake wherever the shoreline is suitable. Up to 2016 onshore grazing has not been a major problem. In 2017 despite careful fencing animals have been found right down to the water’s edge with devastating results to many areas where good numbers of Spiranthes were emerging. Two sites remain clear from animal damage but in one of these onshore development has destroyed plants and their habitat; this was probably illegal as such activity is not permitted under the Flora Protection Act and bye-laws. There is one spectacularly safe haven on the western shore of the lake (Study Area 2) which we hope can be managed for many years with Spiranthes in mind. Study Area 1 is an isolated wilderness area which we discovered last year and assumed it would be unlikely to be invaded as it did not seem part of any adjoining farm. Sadly this Summer, just as we visited the site, our first job was to drive out a feisty herd of about 30 cattle that had broken into the land a few hours before. The orchids were still there but about half had been irretrievably damaged. We will have to resort to last years data to map this site and to support our belief that this colony (of over 100 specimens) was recently formed by a breach in a lakeshore sandbank creating a small inlet into a flat lagoon where a braided channel was formed with Spiranthes appearing all along the water lines of various branches of this network.Considering the numerous shores all around L. Conn that this plant has occupied and the numbers that could be present (apart from the damage) at this location, it seems that there must be very large quantity of seed becoming available from some source — presumably from the west as this is the most frequent wind? The rapid appearance of large numbers of new plants (single plants) here is markedly different to L. Allen where new colonies were rare and many plants would have a paired new plant, or two, adjacent to the original plant. So it had less seed dependence and more reliance on vegetative reproduction to sustain the colony. This would explain the declining numbers in L. Allen. Numbers in L. Conn seem buoyant but continuing damage to existing sites will reduce the possibility of new colonists taking hold and re-appearing in subsequent years with ‘offshoots’ beside them.
Why are seedlings more abundant in L. Conn?
L. Conn is the closest large population of S. romanzoffiana to L. Allen. These orchids also, by and large, do not seem able to produce seed — the same problem as in L. Allen! At the time of writing the water level is above the height of the plants we recorded this Summer. i.e. the dying flowers would be well underwater! To the west of L. Conn there is no significant source of seed. There is a small lake, Cross Lough, on The Mullet in west Mayo and there is a large lake (Carrowmore Lake) in Erris but the shores of this lake seem largely unsuitable for the species. (More work is needed here.) There is an extensive sheltered mudflat and marshes area east of The Mullet which might be worth an investigation but is unlikely to have a viable stock. Large equinoctial tides would be a risk and we must remember that no seashore based plants have been recorded in Ireland since Drummond made his amazing discoveries in Castletown Berehaven in 1810.To regenerate populations in L. Conn, L. Allen and other western lakes, we can only conclude that large amount of seeds from North American Spiranthes are crossing the Atlantic and that L. Conn is the first suitable landing area for such seeds. L. Conn is also immediately to the east of some significant mountains (> 500 m.) which may precipitate more rain whereas L. Allen is a considerable distance further east with a mixture of lowlands and lower hills (300 m. +) in between. L. Conn therefore has more rain and more wind derived directly from Atlantic weather systems. Some maps indicate that west Mayo mountain chains may experience 30 - 50% more rainfall than the Lough Allen area though this varies enormously from year to year. Also, all of the West of Ireland seems to be experiencing much greater levels of Summer rain and flooding as a consequence of global warming and a shift in the Jet Stream southwards. Possibly a lot of the seed bearing wind and rain is dissipated by the first mountain chain it meets in Ireland, the Nephin Beg range, close to L. Conn?
Mapping of new study areas for S. romanzoffiana distribution, 2016 and 2017:
These maps are produced by combining satellite images obtained via MapBox.com with our field data overlaid using the incredibly handy ExpertGPS software which we wholeheartedly recommend for this sort of work. It is only by presenting spatial and chronological distribution in this way that we can evaluate the reasons behind rarer plants occurring and surviving in widely disparate areas of the west of Ireland. After many years of work we can almost smell where this rare orchid will pop up and we are disappointed if our hunches do not prove to be true! Study Area 2 was such a hunch and is an area that is a little bit hidden from any easy access. But all the factors looked positive so we made the effort and, as soon as we landed on the shore, we were rewarded with a long line of specimens in a row! This was in the Summer of 2017.But firstly we will consider Study Area 1 (L. Conn) shown RIGHT. This provides many clues as to the origin of this sizable colony of S. romanzoffiana.
Study Area 1.
North East shore of L. Conn, 2016/2017
There were 135 specimens present in this site in 2016. (Each green dot represents 1 specimen.) Specimens were smallish and almost all single stemmed. This implies that this is a new colony and there was no evidence of previous years leaves though these could have been washed off the specimens by winter flooding. The Habitat:Many specific and special circumstances apply to this site. It is a blind bay at the north east corner of the lake so southerly or southwesterly winds blow in here with some force. This has led to a serial deposition of sandbanks and and breaching of those sandbanks. The aerial photograph reveals that this is a very sandy and shallow bay. The red dotted line marks the edge of the water when we visited — lower than when the photograph was taken.3 Lagoons:The evolution of this site is the story of 3 small lagoons all under a hectare. We estimate the New Lagoon is newer than the Dry Lagoon to its east. This is based on the condition of the substrate, the type of vegetation present, and the presence of permanent water. The Dry Lagoon had no surface water and the sandy patches remaining were dry and hard. These conditions do not suit a water loving orchid so none were found apart from 3 on the boundary between this lagoon and the New Lagoon. There was no normal channel for water flow into the dry lagoon. New Lagoon, on the other hand, had an active network of little drains with water running out of the lagoon and back into the lake. There was no ingress of water from the lake at the time of our visit but this would have occurred readily through the open lake entry channel had the water level been slightly higher. We believe the New Lagoon must have been created within the past 3 - 5 years and has remained open to the lake for the past few years, thus providing the ideal wet, almost flat channels with some small banks along which Spiranthes seed could be deposited. As can be seen S. romanzoffiana seeds have settled in a widespread pattern presumably reflecting water height at the time. Seed would have been gathered on the main lake and then flowed in rapidly whenever the water level was high enough and left to settle along the braided channels of the lagoon as the water again receded. Over on the western side of the bay we have named a water-filled lagoon as Clearwater Lagoon. Of course all the lagoons are freshwater but this lagoon was basically a clear-water pond with permanent shallow water and associated water plants growing in it… but no Spiranthes and no drain to the lake under normal circumstances!The red dotted line shows approximately the water level at the time we visited the lake. There was a steady trickle of water coming out of the New Lagoon but none coming from Dry Lagoon. It seems that Spiranthes seed having been concentrated on the wide water body of L. Conn may have been moved north by southerly winds and wave action and, as the water level built up in this bay, water would have burst in and created the new lagoon effectively dispersing seed on very suitable waterside channels and low banks.
Study Area 2.
Lough Conn, West shore
North end of bay.
South end of Bay.
This is a different story but equally supportive of the theory of wind and water borne seed dispersal of S. romanzoffiana. This site is exposed to winds of a southerly and easterly direction — not the prevalent wind source in Ireland but not rare. The pictures shown are of the same bay. The area between the north (LEFT) and south sections had few orchids. This whole shoreline has a very consistent ecology — a gently sloping shore sandy towards the north and more stony on the southern section but with occasional muddy/silty stretches and a few short areas where the shore was largely overgrown. There are other large colonies of Spiranthes north and south of this section.GPS data confirms initial impression… all the orchids are growing in a curve parallel to the shore! At the time of our visits, nearly all the plants were dry and within 1 - 2 m. (horizontally) of the water. There were also quite a few specimens further in from the shore, bigger, healthier, near Alders, and in long grass. Were these more mature specimens or was their vigour and height due to the degree of protection and the need to outgrow the grasses if they were to flower?This Study Area contained 113 specimens all counted by GPS. Just as the braided distribution of specimens in Study Area 1 supports the theory of wind borne colonisation, it seems that the strict linear placement of specimens on this shore reflects the clean border between lake and land and the gently and consistently sloping geography of the shore. There were, however, some very considerable beneficial factors here. Behind the specimens there was an almost continuous strip of grassland and then a dense band of Alders. Everywhere we have seen S. romanzoffiana Alders have been a benign presence. Is this from enriching the soil through the amazing property of Alders to provide nitrogen for poor soils? Or could this also benefit the mycorrhizal associates that are needed for S. romanzoffiana to germinate?The other beneficial factor is that the northern section of this shore is protected by a coniferous plantation whilst the southern section is similarly protect by a significant broad-leaved woodland. As a consequence there were no signs of farm stock which are proving to be a big threat to Spiranthes in other parts of L. Conn in the past couple of years. This is the only site on L. Conn where it seems that there is no imminent human threat to the survival of the species. Possibly a global warming threat (rising water levels) but no clear danger pending at least until the plantation is cut down. Even then the significant Alder fringe should still remain in place?
Conservation potential of these two sites?
The Flora Protection Order (S.I. No. 356/2015 - Flora (Protection) Order, 2015) publishes a list of plant species protected by the Irish Wildlife Act (Wildlife Act 1976) making it an offence to harm these species or to disturb their habitats. S. romanzoffiana, thankfully, is one of the species listed. Such plants are also an asset in that farmers, or other persons, wishing to avail of the GLAS Agricultural Grants Scheme can claim a legitimate conservation concern if they have this species on their land and are protecting it from grazing etc.Sometimes it seems important to establish a special conservation area for these isolated outliers of Spiranthes that now occur in Ireland and Scotland. This seemed very urgent in Lough Allen when numbers seemed to be steadily declining but less so in Lough Conn where numbers were much greater (in 2016), water level is slower to rise, and onshore grazing seemed less of an issue. Study Area 2 area is well protected by virtue of forestry and established woodland on the private land. Hopefully it may survive for many years and provide an opportunity for much appreciated life history study. But, we felt the same about Study Area 1 and this has proved to be vulnerable to sudden devastating invasion by large numbers of cattle? This had the appearance of an uncontrolled escape rather than planned extra grazing. i.e the invasion was planned by the cattle rather than their owner? It would be worth securing this site for Spiranthes conservation; it is of negligible farming value and could be beneficial as a wildlife habitat. However, the very history that made it a unique focus for this orchid could easily destroy it again, though if it was managed sympathetically in partnership with erosion and natural change it might benefit from further lagoon formation over many years providing a dynamic but ever changing haven for Spiranthes in L. Conn. It is a mere 1 ha. in area plus some other adjoining land that might have potential for a S. romanzoffiana and wildfowl sanctuary — left natural and ungrazed. The ownership of this area is unclear —if not lost!
Other records from L. Conn.
This map outlines the distribution of S. romanzoffiana around L. Conn in 2016 and 2017. In total 635 specimens were found and recorded, mostly in flower. The vast majority of our data comes from 2017. All sites shown have been visited this Summer. The reason for using 2016 data for the north end of the lake is unexpected severe damage due to grazing in 2017. BLUE DOTS = 2017ORANGE DOTS = 2016RED DOTS = 2014/2017Both sites were damaged but c. 50% of the specimens were damaged or destroyed in Study Area 1. This led to a lower count but allowing for eaten and trampled specimens it seems that the same number were emerging as in 2016… hence the use of that data.
Seed Production Report:
All 635 plants recorded here grow at the waters edge. The water level in late July to mid August ranged from 11.2m - 11.5m OD (above sea level). At the start of the survey period nearly all plants were clear of the water but close to it. By mid August most specimens were standing in water but not submerged. At this stage our final search for seed producing specimens was undertaken. None were found. A trip planned for mid-September did not take place as the water level was then at 11.66 and steadily rising as Ireland’s Autumn becomes ever more wet! All plants (that we know of) would have been submerged at this level. This is a typical end of season pattern in the West of Ireland and becoming ever more prevalent in the past 10 years
Damage to existing stock:
Whilst natural factors such as weather are frustrating in that they limit the ability of Irish S. romanzoffiana specimens to reproduce by seed, and this limits the populations viability, it is, particularly, unfortunate that sizable parts of the population at the north end of the lake are now suffering destruction in their natural habitat partly by more animals being allowed onto the shore (horses and cattle) and partly accidentally by cattle breaking through fences.With their status as a Protected Species in Ireland, they should be immune to this problem. It is a valuable and special plant and it does need protection.
Lough Conn displays a vibrant population of S. romanzoffiana, albeit under threat from onshore grazing. Lough Allen always had the impression of a marginal exposed stock at the edge of their range very vulnerable to change. We never proved seed setting in any of the plants examined (without harm) at Lough Allen. Over the period of work there, Summer rains rapidly became an unwelcome feature after a few years of pleasant traditional dry Septembers. The months of September and October are critical for setting of seed and nowadays many of the Lough Allen orchids would be underwater for an extended period before the seeds would be ripe!If fertilisation plus seed formation are exceptionally rare in the Leitrim climate how come this stock survived for probably at least 20 years — maybe greatly longer?
Existing colonies of S. romanzoffiana can survive and replicate themselves organically, i.e. without seed. They do this in a process similar to Daffodils, though daffodils are bulbs whereas Spiranthes is an enlarged root. However it will still produce a secondary shoot alongside the main flowering shoot and this can well last for 3 or more years if undisturbed. We call these offshoots… ‘lateral buds’. When an area is well studied it is quite common to recognise a cluster of Spiranthes plants that are clearly the same grouping as seen 2 or more years before — like the group shown below LEFT.
Study of Spiranthes romanzoffiana vegetative reproduction:
We have carried out a 3 years study of the four errant Spiranthes found on the high ground at Derrintobber (L. Allen) after some Autumns of heavy rain. The best way to see this process in action is to download a PDF we produced on this work which shows the 4 plants over 2 years and how they survived the Winters and flowered again in subsequent Summers. This species seems to have a natural life cycle above ground of 3 or more years if left undisturbed.
NOTE: We advise saving this file to your computer and then opening it with Adobe Acrobat when the small images can be enlarged 4-fold.Unfortunately, intensification of agriculture has put pressure on grazing and cattle and sheep are often found on Spiranthes shorelines, with disastrous consequences. The study specimens were protected for 3 years with basic teepee type structures which kept most grazers away and enabled us to get some very interesting insights into this method of reproduction, and the survival of established plants underwater for long periods of Winter months. They seemed to be perfectly at home and it did protect them from frost and ice. These, however, are now a rare phenomenon here — though all of L. Allen endured a deep long cold spell in 2010.Vegetative reproduction will not sustain a population that is under threat either from flooding or grazing nor will it rapidly expand a population outside its existing colony. Particularly in Lough Conn, striking large and isolated colonies are springing up on all 4 quadrants of the lake. This implies plentiful seed. Where is this coming from if Irish flowers are widely being destroyed by damage to the shoreline, Summer flooding, or simply the weather becoming cold too early and the plant withering and declining without developing any seed? There must be a vibrant source of seed available to L. Conn and there are no other colonies or lakes particularly in the ideal location to the west of L. Conn. The next colonies would be in Canada and America and we think this is where our replacement source is coming from!A distinctive group of 4 vegetatively produced S. romanzoffiana seen at L. Cullin for the past 3 years…
The rate of vegetative reproduction.
It takes a year for a lateral bud to issue from an existing plant and then mature either as a flowering plant or a non-flowering plant. We have seen up to 3 lateral buds on certain plants. We use the term lateral bud as the new generation seems to issue from the stem of the old plant (or its attachment to the root) and is normally just one or two buds making the name ‘rosette’ a bit inapt in the Irish situation? Reports of much greater numbers of lateral buds occurring in the North American population are interesting. This, perhaps is another reflection of the better climate and more vigourous plants occurring in Canada and, particularly, USAThe image shown (RIGHT) appears to show a lateral bud forming on a Mayo specimen this year. From the study highlighted above we would expect these new plants to survive for at least 3 years, if left undisturbed. In any population we have examined 25% of plants would be producing one or more lateral buds at the time of flowering. The existing flowering stems re-appear the following year along with their ‘offspring’ and these pairs or groups are very recognisable in the field for however long they survive.This is a viable way to maintain a population in a given area but will not spread it widely nor will it replace plants damaged or lost through habitat or climate change. As the Irish scene is a very marginal one for this species, as is Scotland, it would seem that the species cannot survive based either on vegetative reproduction or locally produced seed but is very dependent on inward migration of seed from North America…
Sexual reproduction and population dynamics.
The late Summer in North American seems to be ideal for this species compared to our changing and increasingly wet Summers. But that is where the species evolved so, presumably, it is adapted to the North American climate in all its diversity. But this is a point we must verify. There is an assumption that eastern continental North America is dry and warm until it suddenly becomes cold and snowy. However the snow arrival seems to be fairly late in the Fall and may provide more space for Spiranthes romanzoffiana to grow and flower and fertilise and produce seeds and for those seeds to be dispersed in the wind.How does that seed supply populate our lakes when it reaches Ireland (or Scotland). Growing a new specimen from seed is a complex process. Orchids need a mycorrhizal associate to enable the seed to survive in the soil. This is a common arrangement with many orchids and ‘people often say ’that Spiranthes seeds need five years for the plant to grow underground nurtured by its fungal associate’. Without this mycorrhiza the orchid will not survive. But is this associated fungus specific to each species of orchid. Some say it is but other more esteemed opinion says that there is a wide variety of suitable associates in the soil particularly if the seed lands in soil that has (or recently had) a Spiranthes or an orchid colony growing there.Most of the populations we have studied have had a continual presence in a particular area save where terminal damage was done to the habitat. However, one colony, in south west Lough Allen was very successful for a number of years and then disappeared only to re-appear in smaller numbers 5 years later — this would have been a site periodically overgrown but often with bare ground, either natural or man-made, attractive to seed! S. romanzoffiana is an opportunistic coloniser of bare or flattened land, even if it is only the edge of a car park. So, was this a colony that died out (flooding, overgrowth, grazing) and was replaced with new seed, and plants, 5 years later? Or was it possible that the plants survived underground until better conditions arrived. One of the mysteries of Spiranthes!Clearly seed based plant production is essential to explain the varying and sometimes abundant displays of Spiranthes romanzoffiana both here and in Scotland and, it seems, that the vigour and number of our own plants is not great enough to provide that seed not to mention the difficulty dispersing seed if the plants become flooded at a crucial stage. We will discuss the American climate and conditions for seed setting in the next section. If this proves benign then there seems little ground to refute the theory of wind-borne population supply from across the North Atlantic.
Evidence of seed production in Irish S. romanzoffiana.
From what we know of fertilisation and seed production in this species, they need a good two months after flowering to produce viable seed. This, of course, is Irish speculation with Irish weather. Flowering can start as early as mid July and persist to late August. Flies would regularly be seen in Spiranthes flowers during this period, bees less frequently of late. Whether these are effective pollinators we do not know. However, the end part of the process seems very much more critical than the fertilisation stage. We have a much more variable Summer climate in Ireland and, regrettably, it seems to be getting wetter and cooler. The popular Irish phenomenon of an ‘Indian Summer’ (i.e. a warm dry sunny September) seems to be becoming a memory of our childhood. It is frightening to see signs of climate change at such a microscopic level but conditions in the west of Ireland in September can be cold wet and many lakes will be flooded or rising rapidly. Consequently, many of our best Spiranthes can finish (or start) their flowering season under water. A recent German visitor resorted to taking pictures of flowering Spiranthes using an underwater camera!We have sought to monitor developing flowers into the Autumn. However by the time of the final survey (late September) all the specimens we are watching are routinely underwater. We tend to assume that any developing seed within the ovaries will be destroyed if submerged for an extended period? Some flowers flattened by flooding were examined in early September. They seemed slightly enlarged but in no way swollen. No seeds were found!
Is the Irish stock self-contained?
We don’t see how it can be? In over a decade studying the species we don’t believe we have ever seen a seed bearing plant. We have seen swollen ovaries as shown in the photograph, above, but these may not be significantly so as the absence of the flower shows off that organ more prominently and damaged plants (such as this) have not been proven to carry seed. We have no direct contact in Ireland or Britain that has convincing evidence of seed production. (If we are wrong in that statement… we would love to hear from you!) We attribute this lack of seed not to poor fertilisation — though that may be an increasing factor also — but to poor weather in the following months. Cold August and September causes plants to stop growing. These are marginal plants here and, one might think, similar to plants growing in a cool wet climate in North America, such as Newfoundland!The pattern of population change in Lough Allen, Co, Leitrim, where we have the longest experience, is cyclical. They were first identified there in c. 2003 and following that a well established colony was found in the southwest corner and we later found a series of small to large colonies along the east shore of L. Allen where the prevailing wind struck and where there were many suitable flat shores. Numbers declined over the years and particularly on the west shore where, by and large, the habitat did not seem ideal for them. For example, the Mountallen site had good numbers in 2008 but then a total failure for 5 years. During this period the landowner made certain attempts to attract them back This was successful and a small colony was re-established there from 2013 - 2016.
Why a cyclical pattern?
There are two current views in Ireland regarding the appearance and disappearance of S. romanzoffiana but these may be quoted opinions more than witnessed or recorded observations? We don’t know…•Spiranthes may survive for 5 or more years in the soil where they were last seen!•New Spiranthes plants resulting from seed may take up to 5 years in the ground to develop a root system sufficient for the production of a flowering spike!If these theories are correct then this could explain why S. romanzoffiana comes and goes on apparently suitable habitats around L. Allen and other sites. The ‘sudden’ appearance of a colony may mean that there has been a good influx of seed from outside the area some 5 years previously. This colony getting bigger and stronger would represent the growth and maturation of the colonising seedlings. i.e. the plants find the conditions good for growth and do not suffer any grazing or destructive weather effect. So, while they may not produce seed, the numbers of individuals in the colony grows continuously for several years. From the studying of overwintering plants, linked above, it seems that there is a natural longevity (call it 5 years maximum?) in the original specimens. This also seems to apply to adjoining plants formed from lateral buds produced by the original unexpected arrival?So can there be a natural lifespan to these plants and if no new seed source arrives that colony will naturally fade away? This would fit in with the pattern of behaviour seen in Lough Allen — but not in the Mayo lakes where the population seems more stable. There is not enough known about either of these communities to prove this supposition but L. Conn would be in a much better position to receive larger quantities of seed from across the Atlantic than L. Allen would! Nor is there clear proof of those two 5yr. Rules listed above.
A specimen from L. Cullin, south of L. Conn,starting to produce lateral buds. (Aug 2017)
E. Success of seed reproduction in North America.We have seen in the review of the Irish population that there is much doubt cast over their independence (or local viability) on this side of the Atlantic. They may, indeed, be fully dependent on some suspected but unproven link to the species’ obvious homeland in the Nearctic. They are merely welcome visitors to western Europe? This brings up the whole question of the viability of seed production in the North American continent. We have seen pictures of the species from Labrador (very like our own) and from California and Wyoming (amazing strong plants) with multiple stems in a clump! But can that seed be produced abundantly and can it cross the Atlantic — it certainly is light enough and it seems the most plausible explanation for the rather unique pattern of distribution of this transatlantic species.
Comparative life-cycle of Canadian or American S. romanzoffiana.
Contact is being developed with dedicated field botanists and photographers in many areas of North America. There help with this project is much appreciated and their pictures will not only make this page more attractive to read but also greatly add to its scientific validity by sharing information on aspects of this species life history that we can only guess at in Ireland. We are not unduly concerned about intraspecific DNA variations. These can create unneeded difficulties and may be wrongly interpreted. In any group of plants, particularly orchids that grow widely apart and isolated, one can expect some genetic variation. Take for example the two photographs reproduced below. One is from the Yukon, the other from Newfoundland. Other populations occur all the way between these two points and further west into the Aleutian Islands. It seems unlikely that seed would travel from the western US coast but it seems highly possible that if seed were produced in Newfoundland or Labrador in vast quantities that it could easily come straight to Ireland. Our air transport flies over these Territories and flight time often benefits from the Jet Stream that often traverses a route from Newfoundland to western Ireland or Scotland. We hope to prove in this section that seed is regularly produced, ripened and released in Newfoundland and, hopefully, learn the days and weather conditions during such seed dispersal. This will greatly strengthen our thesis that our Spiranthes populations are regularly and continuously topped up by seed from North America. Where DNA might prove useful, is in determining if S. romanzoffiana plants in Ireland are ancient stock or are of recent origin. More of this later…
Seed being produced in the Yukon
A seed head from Grates Cove, Newfoundland
We are particularly glad to have these photographs. They do provide clear evidence that an abundant source of seed may be readily available.(LEFT) YUKON, 5th August 2007This image is from the CYSIP, a group of keen naturalists based in Central Yukon between parallels 63 and 66 south of the Arctic Circle and between Northwest Territory and Alaska. It is much further north than Ireland. However, the Canadian Summers are renowned for having better weather conditions than the wet Irish Atlantic climate. This plant is proof of this…The Central Yukon Species Inventory Project researches all forms of life within its area. This photograph shows a much more advanced plant (especially for the 5th August) than the Irish specimen shown above. The lower capsules are evidently full of seed and, if you look at the larger image ribbing of the ovary can be seen and the capsules seem about to burst open.Many thanks to Lyndsey Larson, Lead Volunteer CYSIP (Central Yukon Species Inventory Project) for the use of this picture.This is an amazing voluntary project mapping the wildlife of central Yukon. For details find their Website HERE. NOTE: We are not saying that seed from the Yukon may have traveled all the way across Canada and then the Atlantic. The Labrador population is in a much better position to provide such seed; it is just amazing to see the species thriving in so many locations.Newfoundland, 3rd October 2014, Grates Cove, (RIGHT)From Grates Cove in Newfoundland, this photograph shows a much later stage in seed head development than we have ever seen in Ireland. Grates Cove is the nearest point of land to Ireland, slightly south of the latitude of Ireland, but also a very Atlantic climate. Is it a coincidence that it has a large stock of Spiranthes readily producing seed right on Atlantic!Many thanks to the photographer and naturalist extraordinaire, Gene Herzberg, for the use of this photograph.We would totally recommend visiting his amazing collection of wildlife photographs on his Flickr Page.Grates Cove is the most eastern point of Newfoundland, This seed head is full and very dry though it seems that the seeds may not yet have been released but look very ready to be spread wide. We have never seen a seed head such as this in Ireland. Sometimes an indication of swelling may be present by mid September but in October in all recent years when we have studied these plants — all of which occur on lake shores very close to the water — cold and wet weather will have halted development of the plants and often even flooded them. An impossible situation for the generation and release of viable seed.
Further North American research:
To really satisfy ourselves that North American seed is released into the atmosphere in such quantities that wind transfer to Ireland is a realistic possibility — the only possibility — we need some further information. Hopefully this will come from our growing cohort of field botanists. The specific information that, in our view, would copper-fasten this theory is listed below:
•How common is S. romanzoffiana in areas close enough, and with suitable conditions, to release seed into transatlantic winds. (Eastern Canadian provinces and US states)?•How widespread and numerous are such suitable Spiranthes locations.•Does S. romanzoffiana often / routinely / rarely have flowers that survive into the Autumn/Fall and are regularly seen to have seeds?•Do such seeds ripen before adverse weather arrives to damage them. i.e. is global warming having an adverse effect in N. America too?•Is there any / much information on new colonies springing up in suitable habitats where they previously did not occur — evidentially based on wind dispersal (e.g. settlement patterns)?•Are there observations of seed based reproduction within colonies. i.e. too far from a parent to be vegetative reproduction and not from old stock dormant underground?These are all big questions which are hard to answer and we must admit to being very unfamiliar with the S. romanzoffiana natural history in North America. The dominant impression that it gives is one of a much more vigorous plant that is widely reported as not under threat — though protected in other locations. We hope to continue this online work and are very grateful from those correspondents we have already heard from…
Wind Gathering and Transport of seed.
The viability of the theory of wind dispersal of seeds from Spiranthes romanzoffiana across the Atlantic from Newfoundland/Labrador to Ireland and Scotland can be assessed using the 4 parameters listed below:•seed production.•wind gathering.•high atmosphere transportation.•seed deposition in Ireland.
Seed production has been discussed above. Suffice to suggest that it is prolific in many States and Territories of the United States and Canada. Variable productivity and viability may occur in certain regions influenced by climate conditions as we find in Ireland. However it is safe to assume that with such a vast number of seeds released over such a vast continent some may travel beyond their local patch. Even Newfoundland, with climate conditions so similar to Ireland, has a healthy stock of specimens the majority of which produce seed and they also grow away from areas of open water and are not vulnerable to flooding. (Gene Herzberg pers.comm)
This investigates how seed may be lifted from lowland areas (or highland areas) into the cloud layer and upper atmosphere. The weight (bulk) of the seed will be significant in regard to how easily it can get wind borne. Along with S. romanzoffiana we will review 3 other Irish/American plant anomalies. There are 3 other interesting ‘north American strays’ found in the west of Ireland, the Blue-eyed Grass found at Lough Allen, and Pipewort and Water Lobelia renowned from certain sites further west in Ireland. They may all be wind borne to a certain degree but other modus operandi are peculiar to individual species. However, all orchids produce seed specifically designed for wind dispersal. This is done by lightening the seed through greatly reducing its content and also creating a balloon around it to make it fly better! An interesting statistic is available from The USDA (United States Department of Agricultural) which says that there are 1,100,000 Spiranthes romanzofiana seeds in a pound of seed! As opposed to 380,000 seeds per pound for the Idaho Blue-eyed Grass (Sisyrinchium idahoense). So, they are very light… Air delivery should be possible! Basically we are talking about dust which will float in any good breeze.Other species and seed dispersal: Sisyrinchium bermudianaA very familiar plant… Sisyrrinchium bermudiana grows alongside S. romanzoffiana in a very small area of L. Allen, Co. Leitrim. It is a long flowering plant famously producing gorgeous blue flowers and fruiting ‘nuts’ throughout the Summer. So a fresh flower and a ripe seed capsule can be seen on the same plant at the same time. We mention this as Blue-eyed Grass is another species whose status in Ireland is little understood. This species, however, comes from Bermuda rather than North America where several different species are widespread across the continent. Can there be a link? Can its arrival in Ireland be down to the wind too? The article below is reproduced from The Bermudian proudly reporting on one of their island’s special flowers:The plant blooms for about one month. Following the flowers, seed pods develop. These seed pods, when ripe, divide into three sections, liberating a number of small dark-brown round seeds, which fall to the ground. Under normal conditions of growth, the seeds germinate during the following autumn…..In the “Flora of Bermuda” by N. L. Britton, an interesting note appears on this plant. For many years, the Bermuda Sisyrinchium was regarded the same as a North American species, but it was definitely established by Hemsley in 1884 that the Bermuda species was a distinct species. This plant has never been collected as a wild plant elsewhere. The theory was advanced by Hemsley and other botanists that S. Bermudiana originated from seed of an American species, brought to Bermuda by a bird or on the wind, and the plant became differentiated through isolation. Another interesting record is that the oldest specimen of this lovely plant is one collected by J. Dickenson about 1699, preserved in the Sloane herbarium at the British Museum of Natural History.(from Gordon R. Groves, first published in The Bermudian May 1953)Lobelia dortmannaWater Lobelia is another exotic plant of the West of Ireland, growing largely submerged in clear water lakes. It is another native of North America but with a wider distribution in western Europe than other Atlantic species discussed here. It also can flower underwater and produce viable seed which then sinks to the bottom of the lake. Whether plants emerging above water level can release seed to the wind is not clear but this does not seem to be a species with a comparable lifecycle to S. romanzoffiana or the ability to produce so many light weight seeds. It is curious, however, that it shares a similar amphi-Atlantic distribution?Eriocaulon acquaticumPipewort is the last species to consider. Only one species (Eriocaulon acquaticum) occurs in Europe being restricted largely to the Atlantic coast of Ireland but also a native of North America and maybe a colonist to Ireland. The small globular white flowers rising above shallow water are said to be wind fertilised. But whether this means that the seed can be wind blown is not quite clear. The seeds are described as being round and about 0.5mm in diameter?Of all these species Spiranthes romanzoffiana may be the plant with lightest seed and the most readily available seed. It is also, in North America, found in drier habitats and some at a considerable altitude. The other 3 species are very much water plants with flower emerging either under water or very close to the water surface. This would suggest a lot of seeds entering water before they ever have a chance to be picked up by the breeze.
High Atmosphere Transportation.
Some seeds fall beside their parents; others have buoyancy aids or spinning devices to carry them a little further but these appendages mitigate against long distance dispersal — they will be damaged or saturated by water. Such seeds often come from trees like Sycamore or Ash where the need is just to sustain the forest. Smaller herb type plants (such as orchids) produce lightweight simple seeds that are adapted to rise upwards in updrafts of air and may travel 1000’s of kilometers in the wind.Internet searches such as… “wind seed dispersal…” have produced a huge array of technical literature largely irrelevant to natural historians or else unavailable except on the payment of a high fee. (As voluntary plant lovers we can’t agree to such payments.) However we acknowledge many helpful exceptions to this rule, mainly older articles or actual books published 40 - 50 years ago. Also, in seeking North American photographs for this article we have also received great local insights from those people into the life of Spiranthes in North America. They seem surprised to consider the idea that these seeds might travel all the way to Ireland? But their plants grow higher and in drier locations, flower longer and produce abundant dry seed, which is routinely released into the air. With a northerly distribution and considerable altitude they will naturally be exposed to winds whistling through the hills and mountains. This way they gain uplift and a means to enter the cloud layer and maybe even the Jet stream?Pending garnering more information we quote an earlier article we used on S. romanzoffiana migration:“Only occasionally are new colonies [of plants] attributed to natural long-range dispersal, for example, the arrival of an orchid, Spiranthes romanzoffianum, in the British Isles in the nineteenth century by wind-borne seed from North America.…..”“An even rarer orchid in Britain is Spiranthes romanzoffianum, native to wet meadows and bogs scattered widely across North America. Its dust like wind-borne seeds evidently cross the Atlantic only rarely. It appeared in a few wet meadows and bogs in Ireland in the nineteenth century and at a few others in Scotland and England since 1900”Sauer, Jonathan D. Plant Migration: the dynamics of geographic patterning in seed plant species. (ISDN 0-520-06003-2)Another Plant Researcher, Sherwin Carlquist in his website makes some very telling comments, in his Island Biology section, concerning immigrant flora to Samoa and Hawaii…“Most mainland forest tree species have seeds too large or otherwise unsuited to long-displace dispersal by wind currents. Testing my hypothesis, Carolyn Corn (1972) showed that Metrosideros seeds can withstand temperatures as cold as those found in the jet stream and can even withstand exposure to salt water. Orchid seeds are tiny enough to travel in the jet stream, but are probably damaged by such cold temperatures”Sherwin Carlquist. Plant Discoveries. (www.sherwincarlquist.com/index.html)We have always assumed that orchid seeds would be able to travel, for a considerable distance, in the jet stream (or any strong breeze) but would have some reservations about them all being damaged. The time spent in the jet stream could be minimal, many seeds are quite hardy and, anyway, what temperature is the jet stream at as it traverses the Atlantic?Carlquist does make a good point. Today conditions in the upper atmosphere are as follows. (data courtesy of Met Eireann, www.met.ie)JetStream information (7th October 2017)HeightTemp ° CPressure (hPa)Ground1410223 km07005 km-810 km (Jet stream height)-50250The jet stream speed today is c. 180km/hr but highly variable. It is located over Ireland and Newfoundland
Cold weather, freezing and orchid seeds; work from Kew Gardens, London.
As you may guess we are researching as we write! The data above is salutary. The figures in red would seem to represent a problem in justifying the jet stream as a means of dispersal. The 10km height data above represents the normal height of the jet stream in the North Atlantic. It is roughly aeroplane height and can greatly speed travel from North America to Europe if conditions are right. Could orchid seeds stand that temperature and low pressure for 15 hours — the time taken to travel from Grates Cove in Newfoundland to Lough Conn, Co. Mayo, Ireland at a Jet stream speed of 200km/hr?Also, research being done in Kew particularly relates to wind dispersal in orchid seeds and is very relevant to the above opinion. We have linked the site as there are many salient comments, research results, and amazing photographs that seem to refute the view that cold upper atmosphere exposure might be lethal. Spiranthes might well survive that journey! A small section of their article is reproduced below but please click on the link provided; it is a wonderful Blog.
Many thanks to Kew Gardens Blog (Wolfgang Stuppy) and The Milennium Seedbank (Tim Marks)
‘The reduction in seed size and weight is mainly achieved at the expense of embryo and endosperm, the latter failing to develop in orchids. At the time of dispersal, orchid seeds consist of a spindle-shaped, wafer-thin seed coat that encloses an extremely small and simplified embryo in the shape of a spherical cluster of cells. Just one single cell layer thick, the seed coat (also called testa) forms a balloon around the embryo, a clear adaptation to wind dispersal.
Orchid seed research at the Millennium Seed Bank
'Being wind-dispersed, orchid seeds are naturally dry at release and appear to be desiccation tolerant. The latter is essential for us to be able to preserve them under very dry and very cold (freezing!) conditions, as we do with other seeds in the Millennium Seed Bank.'Unfortunately, orchid seeds have the reputation to be short-lived under seed banking conditions. Our research is engaged in finding out why this is and how we can extend their survival.‘A basic concept in understanding their specific requirements for storage is to test the relationship between temperature and moisture content upon viability and germination. By running long-term storage experiments with temperatures between -196°C (liquid nitrogen) and +20° (ambient), and a variety of moisture contents, it is possible to identify species-specific requirements.
After reading the above article from the Millennium Seed Bank, we contacted one of our helpful contacts in Canada. This was late in the season when we knew all flowering specimens in Ireland were flooded and their seed heads destroyed. He immediately offered to go to a place in the interior of Newfoundland where he knew S. romanzoffiana occurred and where, like most of that Province, the plants were not exposed to flood risk. He kindly collected some samples and posted them to us which we duly examined and photographed. This was something we had never succeeded in doing with our Irish population.
Photographing two Orchid species seeds:
What first caught our attention on the slide was the ‘invisibility’ of the S. romanzoffiana seed. Doubtless keener eyes might have detected them but we couldn’t. They are tiny! Best picture we could get is shown RIGHT.On the other hand the Broad-leaved Helleborine seeds, which we collected from a local Park, are quite visible to the naked eye. Both sets of photographs were taken at the end of October but the Helleborine was still strong and healthy and shedding its seed naturally on a calm sunlit day — we could see the seeds drifting like golden specks in the low evening sun.Spiranthes seeds were few and mostly damaged as the capsules were obviuosly weathered and the plants had been exposed to some harsh weather. But these are the first seeds we have ever seen from this species.They came from Newfoundland to Ireland, not by wind, but by Canada Post!
Seed deposition in Ireland and within N. America.
Should we be considering deposition of long distance seeds within North America — or from North America?The answer to both questions seems to be Yes, but using different processes? It is harder to prove that North American stock is wind dispersed as it may just be locally produced seeds. The distribution there is totally different to their occurrence in Ireland. In Canada from both Newfoundland and Labrador to the Yukon — two very different habitats — we are assured that plants grow away from water, are not exposed to flooding and tend to have a naturally random placement. i.e. at differing heights, on slopes, and wherever the seeds fall! All correspondents report S. romanzoffiana in varying conditions, in isolated pockets, sometimes at considerable heights, and all readily setting seed in the Fall. So they may be wind dispersed but are clearly not water settled.But in Ireland, the same seed(?), is clearly deposited using water as a collection and settlement medium. All seeds and seedlings produced at one time will be at a consistent height and adjacent to a significant water body. Our 3 maps above, with the vast amount of data included, clearly support this mechanism. Dispersed seed enters a lake through rainfall. Then, depending on water height and wind direction, seed is gently placed on a sand or muddy shoreline and dries out as the water level recedes leaving the seed to get buried and start to grow in conjunction with mycorrhizal fungi.Presumably, if seed is carried across the Atlantic in strong winds it will fall indiscriminately on mountain and bog regions also. However the chance of them germinating in such an overgrown habitat, without the concentrating effect of floating on still water, seems highly improbable. But, some literature does refer to them occurring in bogs in both Ireland and Scotland. We have never seen this! The ubiquitous distribution in Ireland is on lake shores; they can be grassy or rocky or sandy, as long as other vegetation is not too dense.
Any other possible means of dispersal?
There is some evidence from North America of epizoochoric dispersal of seed. i.e seed being carried by birds and other animals either internally or using a seed structure suitable for attachment to the feathers of Geese, for example. But these are different plant species and the migration is north - south along the continental margins of North America. The geese referred to are Brent Geese and White-fronted Geese. A race of the White-fronts occurs in Ireland and is known as the Greenland White-fronted Goose. However this does not migrate through continental North America and its normal migration route is across the Greenland Ice Sheet from its breeding grounds in south west Greenland, to Iceland, and then on to Ireland. This means that it would never encounter Spiranthes romanzoffiana which does not grow in Greenland.This is certainly a successful way of distribution of both seed and fruit producing plants where the plant and animal species meet and where means of carrying the seed can be determined, as is water distribution for large shelled fruits such as the Coconut and quite possibly the normal distribution mode for Water Lobelia and Pipewort species discussed above.
Further proof of such a model.
It is going to be hard to find seeds in a lake; they are absolutely tiny. Our most likely proof lies in more detailed analysis of settlement and survival patterns of Spiranthes and an intensified effort to establish seed production in Ireland. Or, more specifically, to prove beyond reasonable doubt that it so rarely occurs as not to contribute to the continued success of this amazing orchid as part of the Irish Flora. It seems that this plant may not only have originated in North America but is continuously having its population strengthened and renewed from that source.It’s a wonderful world… eh?
Of course there can be no conclusion, not from this combination of observations and hypotheses. There is some evidence but not conclusive evidence. Conclusive evidence to our mind would require proof of Spiranthes seeds in the air and landing in Ireland! How would we get such proof? Spores and bacteria have been found in rain and on planes and high altitude balloons but little reference to seed — no matter how tiny. Carlquist assures us that orchid seeds are small enough to be carried by wind but he raises legitimate concerns about whether they might survive the conditions at the altitude of the Jet stream. But research in Kew suggest that they are designed for long distance dispersal and their very stripped down diaspore might indeed make them tolerant to freezing?However, the circumstantial evidence is very strong and this article does not purport to be either a ‘scientific paper’ or a legal enquiry. We just are driven to explore a curious anomaly. It may point us to where to seek the truth but we should not automatically resort to DNA analysis or seek to distinguish sub-species where there may be simple variation perhaps based on climate or habitat. Big plants grow small in hostile conditions. Perhaps the best thing to do is to summarise our observations and our evidence in a few short lines.•North America is the homeland of this species.•It occurs elsewhere only in Ireland and Scotland.•Populations in Ireland and Scotland have proved erratic.•There seems to be an increase in occurrence, and in big numbers, in sites further north in both countries?•The habitats are remarkably different in North America (wet, dryish, high ground, meadows, forest and lakes) and in Ireland — restricted to lowland lake shores.•In US and Canada, plants are not so exposed to risk of flooding which is ubiquitous in the Irish province. People seem surprised when we lament our flooded plants?•Where it is abundant, in North America, specimens set and develop seed from early August until October and that seed is not destroyed before release.•The climate and environment of Newfoundland is similar to Ireland, cold and wet, yet most Spiranthes set seed there — but not in Ireland?•The one significant difference between Ireland and Newfoundland is that many specimens there do not grow near water.•A plentiful supply of seed exists in Grate’s Cove (see photo above) and other easterly parts of Newfoundland where wind and weather patterns would support seed uplift and direct movement to Ireland.•There is evidence (from Kew) that orchid seeds can tolerate extreme cold.•In Ireland we are not aware (yet) of Spiranthes romanzoffiana occuring on the western coastal fringe, but east of the first mountain chain in Mayo a large population exists in L. Conn. Is this due to mountain watershed?•In L. Conn the pattern of occurrence is PROOF of deposition from water and by water flows. We believe this evidence is conclusive. (See maps.) Similarly in L. Allen.•There are no records of Spiranthes (that we know of) on Irish bogs or hills or any distance removed from a major water body.•We know of no random or steeply sloping distribution of plants in Ireland. •There is evidently an abundant source of seed to produce a good population around many diverse parts of L. Conn but no proof of seed production in that area.•In many parts of North America the species is abundant right up to the Atlantic shore, in L. Conn it is plentiful, L. Allen scarce, and unknown (or extremely rare) further east in Ireland. Similarly in Scotland. Does this reflect a pattern of the natural wastage of seed the further it is carried — some transatlantic seed being preferentially deposited on the first significant land mass westerly winds encounter and deposition lessening going east as rain and seeds die out?Finally, we feel that wind dispersal of S. romanzoffiana to Ireland and Scotland is more likely than any other explanation for this age old mystery. Perhaps climate in the past produced more endemic plants but at present the possibility of local seed production does not seem to explain the readiness with which new colonies form and re-appear in the West of Ireland.David and Frances Farrell, Co. Roscommon, Ireland
Corrections and Additions==========================from: Jennifer Buck-Diaz, California Native Plant Society, 16th October 2017“Thanks for passing on the link to your new page. I can tell you've put a lot of time into this amazing summary. I wonder if you have seen this web resource for species in CA? http://www.calflora.org/cgi-bin/species_query.cgi?where-calrecnum=7741. There are other links to explore from this page as well.Carpenter fen is most certainly not the highest elevation for this species. Our state flora lists the species at no higher than 3300 meters! http://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=45264”==========================from: David, www.WildWest.ie 31st October 2017Epigenetics and S. romanzoffiana. Is this an explanation for variability in this species on different sides of the Atlantic. (PDF)==========================
A perfect Habitat for a near perfect Orchid. Most plants from this area were smaller and on the water’s edge. Stronger plants were further back and in lush grass. But they were all protected by a wall of trees, coniferous and broadleaved, which prevented any grazing or other damage to the many plants along this shore.
A secluded area with many orchids damaged by a cattle break in. Cattle and specimens are shown. Note also stream edge torn up by cattle.
This line of Spiranthes marked a slight depression in the car park where a bundle of Spiranthes had taken the opportunity to settle maybe when the area was flooded
A stunning mature plant from the long established Lough Cullin colony
A. The Plant
B. The Report
C. The Geographical Evidence.
History of worldwide distribution.Personal experience of Irish Distribution.Habitat and topography of Irish occurrences.Habitat and topography of American occurrences.Mapping studies of Irish specimensMapping studies of L. Conn.
D. Reproductive success in Irish plants.
Vegetative Reproduction.Sexual reproduction and Population Dynamics.Is Irish stock self-contained?
E. Success of seed production in North
Comparative life-cycle of Canadian or American S. romanzoffiana.Further N. American research.Wind gathering of seed in N. America.Any other possible means of dispersal?Further proof of such a model.
Lough Conn is a large Salmon and Trout lake set east of the Nephin Beg mountain range and south of Killala Bay and Ballina market town. It contains a large volume of water derived from a wide catchment area and drains to the south via its smaller sister, L. Cullin, into the Moy which then heads back North to enter the sea at Ballina. It has almost flat shores on all sides often sandy or with silty water meadows stretching from a fringe of Alder trees. Ideal Spiranthes country!
Misery Bay, Manatoulin Isl, OntarioLovely flowers but amazing rocks thanks to Per Verdonk (FLICKR) and Creative Commons for making it readily available..This geology is familiar to us. It is known as Alvars in Ontario but we call it karst limestone (eg. The Burren, Co. Clare) and it overlays the underlying granitic Canadian shield. Often found in acidic bases Spiranthes does occur in one limestone lake in Ireland, L. Corrib.Grate’s Cove, NewfoundlandPhoto by Gene Herzberg. Many thanks.We sought this photograph specifically from Prof. Herzberg as it demonstrates the sheer vigour and number of the species that grow and flower and seed in a climate close to the Irish climate and a place directly facing Ireland across the other side of the ocean. View his FLICKR wildlife HERE.
Carpenter Valley fen, Nevada County Eastern California1900m. altitude, Photo courtesy Jennifer Buck-DiazSpiranthes romanzoffiana were common in this fen. Is this their highest occurrence? For further information see her BLOG on the California Native Plant Society website.
Putty Pond, Adirondack Mountains, Saratoga, New YorkPhotos by Jacqueline Donnellyc. 600 m.Habitat and plant photographed by Jacqueline Donnelly. Read about her discovery of S. romanzoffiana in her Saratoga Woods and Waterways BLOG. She has many other Blogs with a passionate description and depiction of the beautiful place in which she lives.
Hubbard County, Minnesotac. 450 mPhoto by Peter M Dzuik of Minnesota Wildflowers. Many thanks to Katy Chayka for her help“Found in northern Minnesota's vast northern swamps and wetlands, Hooded Ladies'-tresses populations are widely scattered and typically few in numbers. There are 5 species of Spiranthes in Minnesota and some can be a challenge to ID.”
Are these ovaries swelling. We imagined they might be. But, having seen images from Canada (below) — we think not!
This is the beautiful Blue-eyed Grass. We include this as it is found in a very small part of the L. Allen shore — where S. romanzoffiana also grows! Can there be a reason, can both be wind derived? This location is not probable for a garden escape. Also this species is ‘bermudiana’ and is not found in North America and as the Newspaper cutting said it is very exclusive to Bermuda so could it have blown from there…
Broad-leaved HelleborineEpipactis helloborine
Once again we are indebted to Gene Herzberg for helping us with this project and must apologise to him for leaving this ‘good idea’a bit late when it was hard to find undamaged seeds. But it’s a start and we are all resolved to tryagain next year.Visit his Flickr collection of Plant and Animal photographs HERE)
Re-evaluating Irish S. romanzoffiana seed production:
After hearing that some Spiranthes seeds were in the Post from Canada we determined to investigate the possibility of such seeds being found in Ireland — especially after finding ripe Epipactis helleborine seeds blowing freely in the late Autumn breeze in our local park. However these are tall plants growing on raised ground and sheltered by trees.We keep regular data on locations and water levels of local S. romanzoffiana sites and, by referring to published water level tables, we can judge how dry or flooded these populations will be. In the first week of November even our tallest plant (40cm. ) would have been inundated on the Mayo and Leitrim lakeside sites that we know.Unfortunately, we know of no site for this species in Ireland that is away from lake shores or on high ground that does not flood!